At which point does the line through $A(4, -1, 3)$ and $B(2, 3, -1)$ have $x$-coordinate 0?

Explanation

1. 01

   The direction $B - A$ is $-2, 4, -4$, so the points of the line are $(4 - 2t, -1 + 4t, 3 - 4t)$.

2. 02

   $4 - 2t = 0$ gives $t = 2$: the point is $(0, 7, -5)$.